No subject

 70.822347 192.168.3.126 -> 192.168.3.5  SIP Request: REGISTER
sip:192.168.3.5
 70.823464  192.168.3.5 -> 192.168.3.126 SIP Status: 100 Trying
 70.823547  192.168.3.5 -> 192.168.3.126 SIP Status: 407 Proxy
Authentication Required
 70.860296 192.168.3.126 -> 192.168.3.5  SIP Request: REGISTER
sip:192.168.3.5
 70.861228  192.168.3.5 -> 192.168.3.126 SIP Status: 100 Trying
 70.861298  192.168.3.5 -> 192.168.3.126 SIP Status: 407 Proxy
Authentication Required
 70.970580 192.168.3.126 -> 192.168.3.5  SIP Request: REGISTER
sip:192.168.3.5
 70.970945  192.168.3.5 -> 192.168.3.126 SIP Status: 100 Trying
 70.971214  192.168.3.5 -> 192.168.3.126 SIP Status: 200 OK
 71.088456 192.168.3.126 -> 192.168.3.5  SIP Request: REGISTER
sip:192.168.3.5
 71.088752  192.168.3.5 -> 192.168.3.126 SIP Status: 100 Trying
 71.088940  192.168.3.5 -> 192.168.3.126 SIP Status: 200 OK
 75.108124  192.168.3.5 -> 192.168.3.126 SIP/SDP Request: NOTIFY
sip:2000 at 192.168.3.126, with session description
 75.133604 192.168.3.126 -> 192.168.3.5  SIP Status: 200 OK
 82.392427 192.168.3.126 -> 192.168.3.5  SIP/SDP Request: INVITE
sip:2000 at 192.168.3.5;user=phone, with session description
 82.393494  192.168.3.5 -> 192.168.3.126 SIP Status: 407 Proxy
Authentication Required
 82.448428 192.168.3.126 -> 192.168.3.5  SIP Request: ACK
sip:2000 at 192.168.3.5;user=phone
 82.493497 192.168.3.126 -> 192.168.3.5  SIP/SDP Request: INVITE
sip:2000 at 192.168.3.5;user=phone, with session description
 82.494235  192.168.3.5 -> 192.168.3.126 SIP Status: 100 Trying
 82.495603  192.168.3.5 -> 192.168.3.126 SIP/SDP Request: INVITE
sip:2000 at 192.168.3.126, with session description
 82.621388 192.168.3.126 -> 192.168.3.5  SIP Status: 500 Internal Server
Error
 82.621816  192.168.3.5 -> 192.168.3.126 SIP Request: ACK
sip:2000 at 192.168.3.126
 82.622283  192.168.3.5 -> 192.168.3.126 SIP/SDP Status: 200 OK, with
session description
 82.751118 192.168.3.126 -> 192.168.3.5  SIP Request: BYE
sip:2000 at 192.168.3.5;user=phone
 82.751681  192.168.3.5 -> 192.168.3.126 SIP Status: 200 OK
 83.629324  192.168.3.5 -> 192.168.3.126 SIP/SDP Status: 200 OK, with
session description